Newborn screening: evolving challenges in an era of rapid discovery

Targeted gene sequencing and hearing follow-up in 7501 newborns reveals an improved strategy for newborn hearing screening

Hearing loss is a common congenital condition. Concurrent newborn hearing and limited genetic screening has been implemented in China for the last decade. However, the role of gene sequencing screening has not been evaluated. In this study, we enrolled 7501 newborns (52.7% male, 47.3% female) in our Newborn Screening with Targeted Sequencing (NESTS) program, and 90 common deafness genes were sequenced for them. Hearing status assessments were conducted via telephone from February 2021 to August 2022, for children aged 3 to 48 months. Of the universal newborn hearing screening, 126 (1.7%) newborns did not pass. Targeted sequencing identified 150 genetically positive newborns (2.0%), with 25 exhibiting dual-positive results in both screening. Following diagnostic audiometry revealed 18 hearing loss newborns and half of them had abnormal results in both screening. The positive predictive value for universal newborn hearing screening alone was merely 14.3% (18/126). However, when combined with targeted sequencing, this rate increased to 36.0% (9/25). Furthermore, limited genetic screening identified 316 carriers of hot-spot variants, but none exhibited biallelic variants. All 15 hot-spot carriers who failed physical screening demonstrated normal hearing during follow-up. In this cohort study of 7501 Newborns, Combining targeted sequencing with universal newborn hearing screening demonstrated technical feasibility and clinical utility of identifying individuals with hearing loss, especially when coupled with genetic counseling and closed-loop management. It is suggested to use this integrated method as an improved strategy instead of the current limited genetic screening program in some regions of China.

The Krabbe Conundrum-How Are Benefits and Harms Weighed to Determine the Net Benefit of Screening?

This Viewpoint explores the conundrum of Krabbe disease and whether it should be added to a newborn screening panel by looking at harms vs benefits.

Parental Preferences for Expanded Newborn Screening: What Are the Limits?

The use of next-generation sequencing technologies such as genomic sequencing in newborn screening (NBS) could enable the detection of a broader range of conditions. We explored parental preferences and attitudes towards screening for conditions for which varying types of treatment exist with a cross-sectional survey completed by 100 parents of newborns who received NBS in Ontario, Canada. The survey included four vignettes illustrative of hypothetical screening targets, followed by questions assessing parental attitudes. Chi-square tests were used to compare frequency distributions of preferences. Results show that most parents supported NBS for conditions for which only supportive interventions are available, but to a significantly lesser degree than those with disease-specific treatments (99% vs. 82-87%, p ≤ 0.01). For conditions without an effective treatment, the type of supportive care and age of onset of the condition did not significantly alter parent perceptions of risks and benefits. Parents are interested in expanded NBS for conditions with only supportive interventions in childhood, despite lower levels of perceived benefit for the child and greater anticipated anxiety from screen-positive results. These preferences suggest that the expansion of NBS may require ongoing deliberation of perceived benefits and risks and enhanced approaches to education, consent, and support.

Pilot protocol for the Parent and Infant Inter(X)action Intervention (PIXI) feasibility study

This paper provides the detailed protocol for a pilot study testing the feasibility, acceptability, and initial efficacy of a targeted two-phase, remotely delivered early intervention program for infants with neurogenetic conditions (NGC) and their caregivers. The Parent and Infant Inter(X)action Intervention (PIXI) is designed to support parents and infants with a NGC diagnosed in the first year of life. PIXI is implemented in two phases, with the first phase focusing on psychoeducation, parent support, and how to establish routines for supporting infant development. Phase II helps parents learn targeted skills to support their infant's development as symptoms may begin to emerge. The proposed non-randomized feasibility pilot study will establish the feasibility of a year-long virtually implemented intervention program to support new parents of an infant diagnosed with an NGC.

A Window of Opportunity for Newborn Screening

Molecular diagnostics and therapies play a central role in an era of precision medicine, with the promise of more accurate diagnoses and more effective treatments. Universal newborn screening (NBS) identifies those health conditions that must be treated in early life and before clinical symptoms become apparent, to maximize effectiveness, prevent morbidity, and reduce or eliminate mortality. However, enthusiasm about NBS as the logical platform for early identification is tempered by the realization that NBS under public health authority exists in a complex ecology in which technology and medicine intersect with politics, ethics, advocacy, and resource constraints-a classic translational challenge that is exacerbated when considering the possible introduction of genome sequencing and molecular therapies in NBS. Substantial change is inevitable if the current model of NBS can be prepared for an envisioned future of greatly expanded molecular diagnostics and therapies. A window of opportunity for modernization now exists, but what changes are needed? The purpose of this commentary is to identify five major initiatives to stimulate focused discussion on how modernization might be achieved: (1) build systems for more rapid collection and integration of extant data relevant to NBS; (2) establish a national network of NBS research centers to design and conduct prospective research studies addressing critical NBS questions; (3) create a network of regional NBS laboratories to expedite state implementation of new methodologies or screening for newly recommended conditions; (4) establish a new stream of federal funding to provide financial support for states and incentivize national harmonization; and (5) integrate solutions in a way that is strategic and effective. Some aspects of these recommendations suggest that radical policy changes are needed to implement molecular testing in NBS and take advantage of emerging molecular therapies. I focus on recommendations for modernizing NBS in the US, some of which may be applicable in other countries.

Expert Evaluation of Strategies to Modernize Newborn Screening in the United States

IMPORTANCE

Novel therapies, including cell and gene therapies, can radically improve outcomes among patients with rare disorders, especially if provided early. Newborn screening (NBS) could support early access to novel therapies, but the speed of new therapy development is a disruptive event for which the public health NBS system and state newborn screening programs are unprepared.

OBJECTIVE

To identify and evaluate possible solutions for modernizing NBS.

DESIGN, SETTING, AND PARTICIPANTS

In this survey study, NBS experts representing clinical research, federal or state advisory boards, patient advocacy groups, industry, or state laboratories completed an online survey in which they considered 20 potential solutions for modernizing NBS and rated each.

EXPOSURES

Participants considered 20 potential solutions in the 5 following domains: (1) timeliness of disorder review, (2) alternative mechanisms to offer screening for new disorders not currently part of NBS, (3) expanded data collection, (4) support for states, and (5) emerging methods of screening and their consequences.

MAIN OUTCOMES AND MEASURES

Mean ratings for each solution on efficacy, acceptability, feasibility, and sustainability.

RESULTS

The survey was completed by 40 NBS experts (median [range] age, 54 [37-73] years; 22 [55.0%] women). Participants acknowledged that substantial change is needed to prepare the NBS system for rapid expansion of novel therapies; on a scale of 0 (no change) to 10 (extensive change), the median (range) score was 8 (2-10), with 18 respondents (45.0%) believing that the NBS would need many new components or an entirely new system to accommodate the changes. All solutions for modernization were considered potentially efficacious by at least 23 respondents (57.5%). The 2 most strongly endorsed were to establish mechanisms for cross-state data coordination for provisional disorders (38 respondents [95.0%]) and create a network of regional screening laboratories (36 [90.0%]). These were closely followed by aligning programs across federal agencies (35 [87.5%]), expanding funding for research (34 [85.0%]), expanding funding to states (34 [85.0%]), building capacity to identify genetic variants and an associated clinical database (34 [85.0%]), and conducting surveillance to study long-term outcomes (34 [85.0%]).

CONCLUSIONS AND RELEVANCE

In this study, there was consensus among experts that NBS needs to change if the system is to be prepared for a rapid increase in transformative therapies. To our knowledge, this is the first systematic inventory of potential solutions for modernizing NBS and expert perceptions of each. The findings suggest that the modernization of NBS will require the integration of highly rated solutions, strategic planning, and coordination among multiple stakeholders.

Newborn screening with targeted sequencing: a multicenter investigation and a pilot clinical study in China

Different newborn screening (NBS) programs have been practiced in many countries since the 1960s. It is of considerable interest whether next-generation sequencing is applicable in NBS. We have developed a panel of 465 causative genes for 596 early-onset, relatively high incidence, and potentially actionable severe inherited diseases in our Newborn Screening with Targeted Sequencing (NESTS) program to screen 11,484 babies in 8 Women and Children's hospitals nationwide in China retrospectively. The positive rate from preliminary screening of NESTS was 7.85% (902/11,484). With 45.89% (414/902) follow-up of preliminary positive cases, the overall clinically confirmative diagnosis rate of monogenic disorders was 12.07% (50/414), estimating an average of 0.95% (7.85% × 12.07%) clinical diagnosis rate, suggesting that monogenic disorders account for a considerable proportion of birth defects. The disease/gene spectrum varied in different regions of China. NESTS was implemented in a hospital by screening 3923 newborns to evaluate its clinical application. The turn-around time of a primary report, including the sequencing period of < 7 days, was within 11 days by our automatic interpretation pipeline. Our results suggest that NESTS is feasible and cost-effective as a first-tier NBS program, which will change the status of current clinical practice of NBS in China.

Ethical implications of next-generation sequencing and the future of newborn screening

ABSTRACT

Over the last 50 years, routine newborn blood screening for congenital disorders has been hailed as a miracle of modern science, saving countless lives by providing a means to detect and treat life-threatening disorders before symptoms present. Despite progress made with more than 5,000 babies effectively identified with rare conditions each year, congenital anomalies collectively remain at the top of the list as the cause of death for babies under 1 year of age, accounting for more than 20% of all infant mortalities. Rapid technological advances have seen the original singular newborn screen for phenylketonuria expand to a core set of 34 conditions and an additional 26 secondary conditions on the Recommended Uniform Screening Panel, with wide state-to-state variation for implementation. As genomic analysis evolves to enable next-generation sequencing, debates continue over the ethical, legal, and social implications of identifying conditions for which there is no effective treatment. Nurse practitioners should be engaged and informed in providing evidence-based support to families engaging in ethical complex decision making surrounding newborn screening while effectively balancing risk-benefit analysis with individual beliefs and values.

Digital peer-to-peer information seeking and sharing: Opportunities for education and collaboration in newborn screening

Parents use the internet to connect with their peers and access information about a multitude of health topics, including newborn screening (NBS). As the NBS system evolves, education about NBS must be evaluated and updated to remain accessible and beneficial to parents. In this article, we aim to describe parents' current NBS educational needs and highlight areas to improve newborn screening education by detailing an analysis of NBS posts on an online parenting discussion platform. We analyzed a total of 317 discussion posts on BabyCenter®, finding that parents had questions about and desired support around many aspects of NBS including processes, results, and follow-up. As a result of this analysis, three recommendations to improve NBS education were developed. Through collaboration and by leveraging technology, we can provide parents with accessible, timely, and desired NBS informational and social support.

Functional Confirmation of DNA Repair Defect in Ataxia Telangiectasia (AT) Infants Identified by Newborn Screening for Severe Combined Immunodeficiency (NBS SCID)

BACKGROUND

The introduction of newborn screening for severe combined immunodeficiencies (NBS SCID) in 2010 was a significant public health milestone. Although SCID was the primary target, several other conditions associated with severe T-cell lymphopenia have subsequently been identified as secondary targets. The differential diagnosis in infants with an abnormal T-cell receptor excision circle result on NBS SCID who do not meet criteria for typical SCID is often broad, and often the evaluation of these conditions requires immunological and functional testing, in conjunction with genetic analysis, to obtain an accurate diagnosis and develop an appropriate management and treatment plan.

OBJECTIVE

We describe here 3 infants identified by NBS SCID, who required additional workup as they did not have a typical SCID phenotype and meet the relevant diagnostic criteria. Genetic testing identified pathogenic variants in ATM in all 3 patients, and the pathogenicity of the variants was confirmed by a functional flow cytometry assay.

METHODS

The patients underwent immunological and genetic workup to identify an underlying cause of their abnormal NBS SCID. Ataxia telangiectasia (AT) was suspected based on clinical and family history, and immunological analyses. The diagnosis was confirmed in all patients with a rapid functional flow cytometric assay and genetic testing.

RESULTS

A rapid functional flow cytometry assay was used as a diagnostic and confirmatory tool, in conjunction with genetic testing, to make a diagnosis of AT. Experimental validation of the causal relationship between genotype and phenotype allowed for expeditious diagnosis, which facilitated early discussions with families regarding prognosis, treatment, and management.

CONCLUSIONS

Even with increased rapidity and access to genetic results, functional testing is required for clinical diagnosis in infants identified by NBS SCID who do not fit into the classic categories or have novel genetic variants to confirm the diagnosis. Consideration should be given to the use of functional assays as an essential component of an integrated evaluation to characterize the genetics and mechanisms of inborn errors of immunity.

Laboratory Diagnosis of Lysosomal Diseases: Newborn Screening to Treatment

The goal of screening programs for inborn errors of metabolism (IEM) is early detection and timely intervention to significantly reduce morbidity, mortality and associated disabilities. Phenylketonuria exemplifies their success as neonates are identified at birth and then promptly treated allowing normal neurological development. Lysosomal diseases comprise about 50 IEM arising from a deficiency in a protein required for proper lysosomal function. Typically, these defects are in lysosomal enzymes with the concomitant accumulation of the enzyme's substrate as the cardinal feature. None of the lysosomal diseases are screened at birth in Australia and in the absence of a family history, traditional laboratory diagnosis of the majority, involves demonstrating a deficiency of the requisite enzyme. Diagnostic confusion can arise from interpretation of the degree of residual enzyme activity causative of disease and is impractical when the disorder is not due to an enzyme deficiency per se. Advances in mass spectrometry technologies has enabled simultaneous measurement of the enzymes' substrates and their metabolites which facilitates the efficiency of diagnosis. Employing urine chemistry as a reflection of multisystemic disease, individual lysosomal diseases can be identified by a characteristic substrate pattern complicit with the enzyme deficiency. Determination of lipids in plasma allows the diagnosis of a further class of lysosomal disorders, the sphingolipids. The ideal goal would be to measure biomarkers for each specific lysosomal disorder in the one mass spectrometry-based platform to achieve a diagnosis. Confirmation of the diagnosis is usually by identifying pathogenic variants in the underlying gene, and although molecular genetic technologies can provide the initial diagnosis, the biochemistry will remain important for interpreting molecular variants of uncertain significance.

Early Check: translational science at the intersection of public health and newborn screening

Background

Newborn screening (NBS) occupies a unique space at the intersection of translational science and public health. As the only truly population-based public health program in the United States, NBS offers the promise of making the successes of translational medicine available to every infant with a rare disorder that is difficult to diagnose clinically, but for which strong evidence indicates that presymptomatic treatment will substantially improve outcomes. Realistic NBS policy requires data, but rare disorders face a special challenge: Screening cannot be done without supportive data, but adequate data cannot be collected in the absence of large-scale screening. The magnitude and scale of research to provide this expanse of data require working with public health programs, but most do not have the resources or mandate to conduct research.

Methods

To address this gap, we have established Early Check, a research program in partnership with a state NBS program. Early Check provides the infrastructure needed to identify conditions for which there have been significant advances in treatment potential, but require a large-scale, population-based study to test benefits and risks, demonstrate feasibility, and inform NBS policy.

Discussion

Our goal is to prove the benefits of a program that can, when compared with current models, accelerate understanding of diseases and treatments, reduce the time needed to consider inclusion of appropriate conditions in the standard NBS panel, and accelerate future research on new NBS conditions, including clinical trials for investigational interventions.

Trial registration

Clinicaltrials.gov registration #NCT03655223. Registered on August 31, 2018.

Dried blood spot compared to plasma measurements of blood-based biomarkers of brain injury in neonatal encephalopathy

BACKGROUND

Data correlating dried blood spots (DBS) and plasma concentrations for neonatal biomarkers of brain injury are lacking. We hypothesized that candidate biomarker levels determined from DBS can serve as a reliable surrogate for plasma levels.

METHODS

In the context of a phase II multi-center trial evaluating erythropoietin for neuroprotection in neonatal encephalopathy (NE), DBS were collected at enrollment ( < 24 h), day 2, 4, and 5. Plasma was collected with the first and last DBS. The relationship between paired DBS-plasma determinations of brain-specific proteins and cytokines was assessed by correlation and Bland-Altman analyses. For analytes with consistent DBS-plasma associations, DBS-derived biomarker levels were related to brain injury by MRI and 1-year outcomes.

RESULTS

We enrolled 50 newborns with NE. While S100B protein, tumor necrosis factor α, interleukin (IL)1 β, IL-6, IL-8 demonstrated significant DBS-plasma correlations, Bland-Altman plots demonstrated that the methods are not interchangeable, with a 2 to 4-fold error between measurements. No significant relationships were found between DBS levels of TNFα, IL-6, and IL-8 and outcomes.

CONCLUSION

Further work is needed to optimize elution and assay methods before using DBS specimens as a reliable surrogate for plasma levels of candidate brain injury biomarkers in NE.

Interpretation of Genomic Sequencing Results in Healthy and Ill Newborns: Results from the BabySeq Project

Genomic sequencing provides many opportunities in newborn clinical care, but the challenges of interpreting and reporting newborn genomic sequencing (nGS) results need to be addressed for its broader and effective application. The BabySeq Project is a pilot randomized clinical trial that explores the medical, behavioral, and economic impacts of nGS in well newborns and those admitted to a neonatal intensive care unit (NICU). Here we present childhood-onset and actionable adult-onset disease risk, carrier status, and pharmacogenomics findings from nGS of 159 newborns in the BabySeq Project. nGS revealed a risk of childhood-onset disease in 15/159 (9.4%) newborns; none of the disease risks were anticipated based on the infants' known clinical or family histories. nGS also revealed actionable adult-onset disease risk in 3/85 (3.5%) newborns whose parents consented to receive this information. Carrier status for recessive diseases and pharmacogenomics variants were reported in 88% and 5% of newborns, respectively. Additional indication-based analyses were performed in 29/32 (91%) NICU newborns and 6/127 (5%) healthy newborns who later had presentations that prompted a diagnostic analysis. No variants that sufficiently explained the reason for the indications were identified; however, suspicious but uncertain results were reported in five newborns. Testing parental samples contributed to the interpretation and reporting of results in 13/159 (8%) newborns. Our results suggest that nGS can effectively detect risk and carrier status for a wide range of disorders that are not detectable by current newborn screening assays or predicted based on the infant's known clinical or family history, and the interpretation of results can substantially benefit from parental testing.

Newborn Screening Collection and Delivery Processes in Michigan Birthing Hospitals: Strategies to Improve Timeliness

Objectives This study aimed to determine which steps in the newborn screening collection and delivery processes contribute to delays and identify strategies to improve timeliness. Methods Data was analyzed from infants (N = 94,770) who underwent newborn screening at 83 hospitals in Michigan between April 2014 and March 2015. Linear mixed effects models estimated effects of hospital and newborn characteristics on times between steps in the process, whereas simulation explored how to improve timeliness through adjustments to schedules for the state laboratory and for specimen pickup from hospitals. Results Time from collection to receipt of arrival to the state laboratory varied greatly with collection timing (P < 0.001), with specimens collected on Friday or Saturday delayed an average of 9-12 h compared to other specimens. Simulation estimates shifting specimen pickup from 6 p.m. Sunday-Friday to 9 p.m. Sunday-Friday could lead to an additional 12.6% of specimens received by the Michigan laboratory within 60 h of birth. Conclusions for Practice The time between when a specimen is collected and received by the laboratory can be a significant bottleneck in the newborn screening process. Modifying hospital pickup schedules appears to be a simple way to improve timeliness.

Evaluating parents' decisions about next-generation sequencing for their child in the NC NEXUS (North Carolina Newborn Exome Sequencing for Universal Screening) study: a randomized controlled trial protocol

BACKGROUND

Using next-generation sequencing (NGS) in newborn screening (NBS) could expand the number of genetic conditions detected pre-symptomatically, simultaneously challenging current precedents, raising ethical concerns, and extending the role of parental decision-making in NBS. The NC NEXUS (Newborn Exome Sequencing for Universal Screening) study seeks to assess the technical possibilities and limitations of NGS-NBS, devise and evaluate a framework to convey various types of genetic information, and develop best practices for incorporating NGS-NBS into clinical care. The study is enrolling both a healthy cohort and a cohort diagnosed with known disorders identified through recent routine NBS. It uses a novel age-based metric to categorize a priori the large amount of data generated by NGS-NBS and interactive online decision aids to guide parental decision-making. Primary outcomes include: (1) assessment of NGS-NBS sensitivity, (2) decision regret, and (3) parental decision-making about NGS-NBS, and, for parents randomized to have the option of requesting them, additional findings (diagnosed and healthy cohorts). Secondary outcomes assess parents' reactions to the study and to decision-making.

METHODS/DESIGN

Participants are parents and children in a well-child cohort recruited from a prenatal clinic and a diagnosed cohort recruited from pediatric clinics that treat children with disorders diagnosed through traditional NBS (goal of 200 children in each cohort). In phase 1, all parent participants use an online decision aid to decide whether to accept NGS-NBS for their child and provide consent for NGS-NBS. In phase 2, parents who consent to NGS-NBS are randomized to a decision arm or control arm (2:1 allocation) and learn their child's NGS-NBS results, which include conditions from standard (non-NGS) NBS plus other highly actionable childhood-onset conditions. Parents in the decision arm use a second decision aid to make decisions about additional results from their child's sequencing. In phase 3, decision arm participants learn additional results they have requested. Online questionnaires are administered at up to five time points.

DISCUSSION

NC NEXUS will use a rigorous interdisciplinary approach designed to collect rich data to inform policy, practice, and future research.

TRIAL REGISTRATION

clinicaltrials.gov, NCT02826694 . Registered on 11 July, 2016.

A next-generation newborn screening pilot study: NGS on dried blood spots detects causal mutations in patients with inherited metabolic diseases

The range of applications performed on dried blood spots (DBS) widely broadened during the past decades to now include next-generation sequencing (NGS). Previous publications provided a general overview of NGS capacities on DBS-extracted DNA but did not focus on the identification of specific disorders. We thus aimed to demonstrate that NGS was reliable for detecting pathogenic mutations on genomic material extracted from DBS. Assuming the future implementation of NGS technologies into newborn screening (NBS), we conducted a pilot study on fifteen patients with inherited metabolic disorders. Blood was collected from DBS. Whole-exome sequencing was performed, and sequences were analyzed with a specific focus on genes related to NBS. Results were compared to the known pathogenic mutations previously identified by Sanger sequencing. Causal mutations were readily characterized, and multiple polymorphisms have been identified. According to variant database prediction, an unexplained homozygote pathogenic mutation, unrelated to patient’s disorder, was also found in one sample. While amount and quality of DBS-extracted DNA are adequate to identify causal mutations by NGS, bioinformatics analysis revealed critical drawbacks: coverage fluctuations between regions, difficulties in identifying insertions/deletions, and inconsistent reliability of database-referenced variants. Nevertheless, results of this study lead us to consider future perspectives regarding “next-generation” NBS.

Fragile X Newborn Screening: Lessons Learned From a Multisite Screening Study

BACKGROUND

Delays in the diagnosis of children with fragile X syndrome (FXS) suggest the possibility of newborn screening as a way to identify children earlier. However, FXS does not have a proven treatment that must be provided early, and ethical concerns have been raised about the detection of infants who are carriers. This article summarizes major findings from a multisite, prospective, longitudinal pilot screening study.

METHODS

Investigators in North Carolina, California, and Illinois collaborated on a study in which voluntary screening for FXS was offered to parents in 3 birthing hospitals. FXS newborn screening was offered to >28 000 families to assess public acceptance and determine whether identification of babies resulted in any measurable harms or adverse events. Secondary goals were to determine the prevalence of FMR1 carrier gene expansions, study the consent process, and describe early development and behavior of identified children.

RESULTS

A number of publications have resulted from the project. This article summarizes 10 "lessons learned" about the consent process, reasons for accepting and declining screening, development and evaluation of a decision aid, prevalence of carriers, father participation in consent, family follow-up, and maternal reactions to screening.

CONCLUSIONS

The project documented public acceptance of screening as well as the challenges inherent in obtaining consent in the hospital shortly after birth. Collectively, the study provides answers to a number of questions that now set the stage for a next generation of research to determine the benefits of earlier identification for children and families.

Willingness to Pay for a Newborn Screening Test for Spinal Muscular Atrophy

OBJECTIVES

The current US mandatory newborn screening panel does not include spinal muscular atrophy, the most common fatal genetic disease among children. We assessed population preferences for newborn screening for spinal muscular atrophy, and how test preferences varied depending on immediate treatment implications.

METHODS

We conducted an online willingness-to-pay survey of US adults (n = 982). Respondents were asked to imagine being parents of a newborn. Each respondent was presented with two hypothetical scenarios following the spinal muscular atrophy screening test: current standard of care (no treatment available) and one of three randomly assigned scenarios (new treatment available to improve functioning, survival, or both). We used a bidding game to elicit willingness to pay for the spinal muscular atrophy test, and performed a two-part model to estimate median and mean willingness-to-pay values.

RESULTS

Most respondents (79% to 87%) would prefer screening their newborns for spinal muscular atrophy. People expressed a willingness to pay for spinal muscular atrophy screening even without an available therapy (median: $142; mean: $253). Willingness to pay increased with treatment availability (median: $161 to $182; mean: $270 to $297) and respondent income. Most respondents considered test accuracy, treatment availability, and treatment effectiveness very important or important factors in deciding willingness to pay.

CONCLUSIONS

Most people would prefer and would be willing to pay for testing their newborn for spinal muscular atrophy, even in the absence of direct treatment. People perceive the spinal muscular atrophy test more valuable if treatment were available to improve the newborn's functioning and survival. Despite preferences for the test information, adding spinal muscular atrophy to newborn screening programs remains controversial. Future studies are needed to determine how early detection may impact long-term patient outcomes.

Ethical issues in pediatric genetic testing and screening

PURPOSE OF REVIEW

Developments in genetic test technologies enable a detailed analysis of the genomes of individuals across the range of human development from embryos to adults with increased precision and lower cost. These powerful technologies raise a number of ethical issues in pediatrics, primarily because of the frequent lack of clinical utility of genetic information, the generation of secondary results and questions over the proper scope of parental authority for testing.

RECENT FINDINGS

Several professional organizations in the fields of genetics and pediatrics have published new guidance on the ethical, legal, and policy issues relevant to genetic testing in children. The roles of predictive testing for adult-onset conditions, the management of secondary findings and the role of informed consent for newborn screening remain controversial. However, research and experience are not demonstrating serious adverse psychosocial impacts from genetic testing and screening in children. The use of these technologies is expanding with the notion that the personal utility of test results, rather than clinical utility, may be sufficient to justify testing.

SUMMARY

The use of microarray and genome sequencing technologies is expanding in the care of children. More deference to parental decision-making is evolving in contexts wherein information and counseling can be made readily available.

Parental intentions to enroll children in a voluntary expanded newborn screening program

BACKGROUND AND OBJECTIVES

Nearly all babies in the United States are tested at birth for rare, serious, and treatable disorders through mandatory state newborn screening (NBS). Recently, there have been calls for an expanded, voluntary model to facilitate early diagnosis and treatment of a wider range of disorders. We applied the reasoned action framework to examine parental intentions to participate in voluntary expanded screening.

METHODS

We recruited a national cohort of recent and expectant parents living in the U.S. who completed a self-administered online survey (N = 1001). Using a mixed-level fractional factorial experiment, we studied parental participation intentions and preferences for timing of consent, cost, consent format, and testing options.

RESULTS

We conducted a hierarchical regression analysis assessing parental intentions to participate in voluntary expanded NBS. Attitudes, perceived normative influence, and perceived behavioral control explained substantial variance in intention, with perceived normative influence emerging as the strongest predictor. We found no evidence that the manipulated program features altered mean levels of intention, but timing of parental permission, cost, and permission format moderated the relative importance of reasoned action constructs on intention.

CONCLUSION

Program design features may impact the psychological mechanisms underlying parental decision making for voluntary expanded screening. These results have important implications for parent education, outreach, and informed parental permission procedures.

Inborn Errors of Metabolism

Inborn errors of metabolism are single gene disorders resulting from the defects in the biochemical pathways of the body. Although these disorders are individually rare, collectively they account for a significant portion of childhood disability and deaths. Most of the disorders are inherited as autosomal recessive whereas autosomal dominant and X-linked disorders are also present. The clinical signs and symptoms arise from the accumulation of the toxic substrate, deficiency of the product, or both. Depending on the residual activity of the deficient enzyme, the initiation of the clinical picture may vary starting from the newborn period up until adulthood. Hundreds of disorders have been described until now and there has been a considerable clinical overlap between certain inborn errors. Resulting from this fact, the definite diagnosis of inborn errors depends on enzyme assays or genetic tests. Especially during the recent years, significant achievements have been gained for the biochemical and genetic diagnosis of inborn errors. Techniques such as tandem mass spectrometry and gas chromatography for biochemical diagnosis and microarrays and next-generation sequencing for the genetic diagnosis have enabled rapid and accurate diagnosis. The achievements for the diagnosis also enabled newborn screening and prenatal diagnosis. Parallel to the development the diagnostic methods; significant progress has also been obtained for the treatment. Treatment approaches such as special diets, enzyme replacement therapy, substrate inhibition, and organ transplantation have been widely used. It is obvious that by the help of the preclinical and clinical research carried out for inborn errors, better diagnostic methods and better treatment approaches will high likely be available.

Whole-Genome Screening of Newborns? The Constitutional Boundaries of State Newborn Screening Programs

State newborn screening (NBS) programs routinely screen nearly all of the 4 million newborns in the United States each year for ∼30 primary conditions and a number of secondary conditions. NBS could be on the cusp of an unprecedented expansion as a result of advances in whole-genome sequencing (WGS). As WGS becomes cheaper and easier and as our knowledge and understanding of human genetics expand, the question of whether WGS has a role to play in state NBS programs becomes increasingly relevant and complex. As geneticists and state public health officials begin to contemplate the technical and procedural details of whether WGS could benefit existing NBS programs, this is an opportune time to revisit the legal framework of state NBS programs. In this article, we examine the constitutional underpinnings of state-mandated NBS and explore the range of current state statutes and regulations that govern the programs. We consider the legal refinements that will be needed to keep state NBS programs within constitutional bounds, focusing on 2 areas of concern: consent procedures and the criteria used to select new conditions for NBS panels. We conclude by providing options for states to consider when contemplating the use of WGS for NBS.

Advanced technologies for the molecular diagnosis of fragile X syndrome

Fragile X syndrome (FXS), a trinucleotide repeat disorder, is the most common heritable form of cognitive impairment. Since the discovery of the FMR1 gene in 1991, great strides have been made in the field of molecular diagnosis for FXS. Cytogenetic analysis, which was the method of diagnosis in the early 1990, was replaced by Southern blot and PCR analysis albeit with some limitations. In the past few years many PCR-based methodologies, able to amplify large full mutation expanded alleles, with or without methylation, have been proposed. Reviewed here are the advantages, disadvantages and limitations of the most recent developments in the field of FXS diagnosis.

Utility of whole-genome sequencing for detection of newborn screening disorders in a population cohort of 1,696 neonates

PURPOSE

To assess the potential of whole-genome sequencing (WGS) to replicate and augment results from conventional blood-based newborn screening (NBS).

METHODS

Research-generated WGS data from an ancestrally diverse cohort of 1,696 infants and both parents of each infant were analyzed for variants in 163 genes involved in disorders included or under discussion for inclusion in US NBS programs. WGS results were compared with results from state NBS and related follow-up testing.

RESULTS

NBS genes are generally well covered by WGS. There is a median of one (range: 0-6) database-annotated pathogenic variant in the NBS genes per infant. Results of WGS and NBS in detecting 28 state-screened disorders and four hemoglobin traits were concordant for 88.6% of true positives (n = 35) and 98.9% of true negatives (n = 45,757). Of the five infants affected with a state-screened disorder, WGS identified two whereas NBS detected four. WGS yielded fewer false positives than NBS (0.037 vs. 0.17%) but more results of uncertain significance (0.90 vs. 0.013%).

CONCLUSION

WGS may help rule in and rule out NBS disorders, pinpoint molecular diagnoses, and detect conditions not amenable to current NBS assays.